This invention relates to the fabrication of board-like products from sugarcane rind fibers.
Recently achieved advancements in the art of sugarcane stalk component separation have rendered highly feasible the individual separation of sugarcane stalk components. These advancements are disclosed, for example, in U.S. Pat. Nos. 3,424,611 (issued Jan. 28, 1969); 3,424,612 (issued Jan. 28, 1969); 3,464,877 (issued Sept. 2, 1969); 3,566,944 (issued Mar. 2, 1971); 3,567,510 (issued Mar. 2, 1971); 3,567,511 (issued Mar. 2, 1971); 3,690,358 (issued Sept. 12, 1972); and 3,698,459 (issued Oct. 17, 1972), all assigned to the assignee of the present invention. By virtue of the methods and apparatus revealed in these patents, the pith, rind, and epidermis portions of sugarcane stalk material may be separately recovered in relatively undamaged condition, thereby maximizing the commercial utility of sugarcane.
Prior to the above-noted advancements, the recovery of sugarcane products involved subjecting the sugarcane stalks to a series of crushing steps that produced a pulverized cane substance termed bagasse. Begasse requires intense processing for the recovery therefrom of juices and other valuable components. The ultimate value of the sugarcane components in the bagasse is restricted due to the destructive effects of the stalk-crushing operations.
Individual separation of sugarcane components made possible by the teachings of the above-noted patents has rendered cane pulverization obsolete. Now the cane components can be recovered in their relatively undamaged natural state suitable for independent processing.
For example, it is now more economically feasible to recover sugar from the individually separated sugar-laden pith component. Subsequent to such sugar removal, the pith fibers, which remain intact, may be processed for the recovery of cellulose. Other parts of the pith may be used in pulp and paper manufacturing operations.
The individually recoverable cane epidermis may be conveniently processed for the recovery of wax products.
The present invention relates to the individually recoverable rind portion of sugarcane stalk material. Sugarcane rind contains numerous fiber bundles, sometimes called fibrovascular bundles, which are groups of elemental fibers in discrete elongated units. The fibers contain natural resinous binder substances which hold the fibers and bundles together. It has been found that undamaged rind strips, recovered through the teachings of the aforelisted patents, can be shredded longitudinally in a manner which loosens or breaks the natural bond between the individual, strand-like rind fibers of the rind strips. In this fashion the individual sugarcane rind fibers can be recovered substantially in their natural state.
It has been discovered that these sugarcane rind fibers have a high longitudinal tensile strength, making them particularly suited for the fabrication of board products. In order to effectively fabricate a board from sugarcane rind fibers, it is necessary to provide fibers which are in a manageable state, properly orient the fibers, and then bond the fibers together. Such steps involve feeding, orienting, and bonding large quantities of randomly arranged, intertwined rind fibers, thus presenting numerous difficulties in being carried out effectively, rapidly and efficiently.
It is an object of the present invention to minimize or obviate such difficulties.
It is another object of the invention to provide board-forming methods and apparatus for rapidly, effectively, and efficiently fabricating boards from sugarcane rind fibers.
It is an additional object of the invention to provide such board products which compare favorably with conventional wooden boards in strength and appearance.
It is a further object of the invention to provide such board products which comprise unitarily bonded sugarcane rind fibers oriented substantially parallel to the longitudinal axis of the board.